Range adjustment for a tilting valve with a floating link operator



United States Patent lnventor Edward H. Short, III

Tulsa, Oklahoma June 21, 1968 Aug. 25, 1970 Combustion Engineering, Inc. New York, New York a corporation of Delaware Appl. No. Filed Patented Assignee RANGE ADJUSTMENT FOR A TILTING VALVE WITH A FLOATING LINK OPERATOR 3 Claims, 2 Drawing Figs.

US. Cl 137/553, 251/86, 251, 303 Int. Cl ..Fl6k 31/52. Fl6k 1/16 [50] Field ofSearch 236/102; 137/553, 556; 251/40, 86, 205, 228, 280, 298, 299, 300, 303

[56] References Cited UNlTED STATES PATENTS 2,518,894 8/1950 Humbarger et al. 3,199,834 8/1965 Short Primary Examiner- Henry T. Klinksiek Attorney Arthur L. Wade ABSTRACT: A tilting valve is actuated by linkage responsive to temperature. The valve tilts on a seat to vary a passage opening for fluid whose supply influences the temperature condition. The passage opening is positioned relative the pivot point on the seat to vary the proportion of the range of the tilt of the valve and the range of the passage opening sizes.

Patented Aug. 25, 1970 NATIONAL ITANK co.

INVENTOR. EDWARD H SHORT 1U ATTORNEY RANGE ADJUSTMENT FOR A TILTING VALVE WITH A FLOATING LINK OPERATOR BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to control mechanisms which modify a fluid flow by a valve in accordance with the variable demand for the fluid. More particularly, the invention relates to positioning the connection of the fluid flow to the valve to predetermine the relation of valve movement by control mechanisms to fluid flow.

2. Description of the Prior Art US. Pat. No. 3,199,834 discloses a tilting valve with a floating link operator. The pivot point of the floating link is established by a manually adjustable mechanism. This adjustment provides the point at which the tilting valve opens to pass a fluid flow through the valve seat. However, the proportions between a range of the variable sensed and the range of fluid flow through the valve is fixed by the constant distance held between the pivot point of the tilting valve and the opening through the seat of the valve. After years of experience with the actual reduction to practice, it has become evident that there are many applications where it is desirable to vary the proportion between the range of the variable sensed and the range of the fluid flow passed through the tilting valve.

SUMMARY OF THE INVENTION A principal object of the invention is to establish a predetermined distance between the pivot point of a tilting valve and the passage opening through the seat of the valve.

Another object is to manually adjust the predetermined distance to fix the proportionality of the range of fluid passed through the valve seat opening and the range of valve tilt relative the seat opening.

The invention contemplates a tilting valve assembly in which the valve seat is comprised of a rotatable fixture through which is formed a passage parallel with the axis of the fixture. Fluid flow to be controlled is passed through the passage as controlled by the tilt of the valve element. Rotation of the fixture establishes the distance between the pivot point of the valve and the passage.

Other objects, advantages and features of this invention will become apparent to one skilled in the art upon consideration of the written specification, appended claims, and attached drawing, wherein:

FIG. 1 is a sectioned elevation of a tilting valve assembly responsive to temperature in which the invention is embodied;

FIG. 2 is a view of FIG. 1 taken along the line 22.

DESCRIPTION OF THE PREFERRED EMBODIMENT- GENERAL ARRANGEMENT In FIG. 1, I have shown the preferred embodiment of my invention in a sectioned elevation of a portion of a temperature controller. The controller is generally similar to that disclosed in my U.S. Pat. No. 3,199,834. FIG. 1, however, discloses only the control head of such adevice. By limiting the drawing to only this portion of the controller, the embodiment of the in vention is more clearly shown with the enlargement permissible.

The invention is also within the valve mechanism assembled within housing 1. This housing 1 is cylindrical in form, one end necked down to threads 2 with which the entire unit is adapted to be mounted in a vessel in which a temperature condition is sensed. The opposite end 3 is open to receive the valve elements within axial bore 4.

The necked down portion with external mounting threads 2 has an axial bore 5 in which the active, primary element of the temperature sensitive element is mounted. Casing 6 is a simple cylinder in form, welded to housing 1 at 7 and elongated to ex tend into the temperature condition sensed.

Link 10 is essentially a plunger fitting within casing 6, attached to a rod 11 extending the length of casing 6 by its one end and extending into housing 1 at its other end. As casing 6 elongates and contracts with temperature variations in the vessel, link I0 is moved to actuate the linkage within housing I.

The purpose of moving link 10 by temperature variation is to actuate a valve controlling fluid which, in turn, controls the temperature variation. This valve is in control head I5, and is shown in its open position in FIG. 1.

Control'head 15 is sized and threaded to couple to the open end 3 of housing 1. Control head 15 is a generally cylindrical body which is drilled to provide a passage for fluid flow into housing bore 4 and a passage for fluid flow out of housing bore 4 and a mounting for a pivot post with which the valve linkage within housing 1 is manually adjusted.

Control head 15 is completely disclosed by FIG. I. The passages drilled in the body of the head can both be seen in FIG. 1. Inlet passage 16 simply directs fluid into bore 4 from a source and outlet passage 17 removes the fluid from bore 4 as valved.

The internal end of passage 17 extends through seat surface 18. This seat surface is on fixture 19 which is rotatable about the axis of control head 15.

Seat surface 18, about the opening of passage 17, is aligned with elongated link 10 as link 10 protrudes from casing 6. Between seat surface 18 and the end of link 10 are arranged the valve element for seat surface 18 and the actuating linkage for that valve element. As link 10 moves toward seat surface l8,'the valve element is unseated from seat surface 18 by the unique arrangement of the linkage between link 10 and the valve element. Further, the point in the movement of link 10 at which the valve element is moved from fullengagement with seat surface 18 is manually established.

VALVE ELEMENT The valve element 25, in elevation, resembles a collar button. The element has a flat surface 26 which rests on seat surface 18 about the opening of conduit 17. From the middle of the round, flat base '27 on which the flat surface 26 is located, a protuberance 28 extends away from the valve surface 26 and seat surface 18.

FIG. 1 shows collar button valve element 25 in an open position to allow flow of the regulating fluid along passage 17 to a regulating, control or like structure not shown. In the closed position, the axis of element 25, passage 17 and link 10 will be aligned. To open the passage 17, valve element 25 is tilted on the circular edge of its surface 26. To tilt the valve element 25 on its circular edge, a force is applied to protuberance 28 in a direction transverse the axis of element 25 and link 10.

Valve element 25 is symmetrical about its axis. The element can be readily turned out on a lathe or screw machine. The element can be rotated to any position about its axis. When the flat base 26 is held against seat surface 18, a transverse force can be applied to tip the round base 27 up on edge from any point on the edge. The edge is held captive by the sloping sides 29 of the counterbore of the face of the fixture 19. The valve element 25 is thus oriented and maintained in a consistent relationship to its seat and actuator, regardless of how it may rotate under vibration or other force applied to housing 1.

FLOATING LINK Collar button valve element 25 is actuated-a transverse force is applied-by a link member extending from link 10 to protuberance 28. FIG. I shows this actuating link 30 in application of a transverse force to valve element 25, and as the connector between link 10 and valve element 25. The elongated form of link 30 is held in operative engagement with the end of link 10 by a spring 31. While moving along the axis of link 10 to keep in operative engagement with link 10, link 30 moves relative to valve element 25 as valve element 25 is held on seat surface 18. Therefore, link 30 is referred to as the floating link of the actuating linkage for valve element 25.

Floating link 30 is pivoted about a point spaced a transverse distance from the axis of valve element 25 and link 10. Link 10, moving along its axis under the influence of temperature, causes link 30 to pivot and swing the end operatively engaged with valve protuberance 28 by an axial hole of link 30 journalled over the protuberence and apply the transverse force needed to tilt valve element 25.

Valve element 25 and floating link 30 are of uniform shape about their axis. Both these parts can be turned on a lathe or produced on a screw machine. Also, floating link 30 can rotate to any position and remain in operative relation to link 10, valve element 25 or its pivot structure. Despite the somewhat unusual impression made upon the eye, this link 30 is simple in operation, easily manufactured, readily assembled and not subject to malfunctioning when jarred or vibrated.

PIVOT STRUCTURE The structure about which floating link 30 pivots is provided by post 32. Post 32 is mounted on control head 15. extending into bore 4 to contact floating link 30 as a pivot. Specifically, point 33 of post 32 is presented to surface 34 of floating link 30. As link moves toward valve element 25, point 33 and surface 34 engage at a position located a transverse distance from the axis of link 10. Floating link 30 pivots, its end swings in an arc and carries protuberance 28 in a direction transverse the axis, and valve surface 26 lifts from seat surface 18 an amount representative of the degree of temperature to which casing 6 is exposed.

Pivot post 32 is threadedly engaged through control head 15. Knob 35 enables the position of point 33 to be adjusted along a path parallel to the axis of link 10 to provide the pivot point for floating link 30 as desired.

FIXTURE 19 In the general description, fixture 19 was referred to as having seat surface 18 thereon. Also, the fixture was described as rotatable and including the internal end of passage 17.

More specifically, fixture 19 is mounted in axial bore 40 of control head 15. A central shaft 41 of fixture 19 extends to the external surface of head 15, through a counterbored passage of bore 40. A cavity is formed between bore 40 and fixture 19. It is with this cavity that passage 17 specifically connects. Further, passage 42 in the head of the fixture is formed parallel to the axis of fixture l9 and by communicating with the cavity becomes the end of passage 17 as generally described.

Shaft 41 extends to the surface of head and is scribed to index on a scale on the surface of the head 15 the distance passage 42 is positioned from the pivot point of valve element It has been previously indicated how seat surface 18 is formed in a recess in the face of the head of fixture 19. The sloping sides 29 can be more specifically described as forming a truncated cone, which in turn forms a junction with surface 18. As fixture 19 is rotated to various positions, various points on this junction become the pivot point for the edge of tilting valve element 25. Regardless of where the particular pivot point falls on this junction as it is moved about the edge of valve element by rotation of fixture 19, the symmetry of the engagement permits a given degree of tilting of valve element 25 to expose varying degrees of opening of passage 42.

OPERATION The general function of this type of control system is covered adequately in my U.S. Pat. No. 3,199,834. The valve element 25 can be appreciated as rotated about its axis, yet adapted to be actuated from its seat with symmetrically uniform effectiveness by the linkage. The linkage is characterized by floating link 30. Link is initially aligned axially with the valve element 25; the two are misaligned by the pivot of link 30 about point 33 of post 32. Link 30 may pivot around a series of points parallel to the axis of the floating link and valve element in their initial alignment, depending on the particular positioning of post 32 within bore 4 by knob 35. Within this general operation of the tilting valve mechanism, the function of the structure embodying the present invention is clearly an advance in the art.

The rotation of fixture 19 determines the distance between the pivot point for valve element 25 and passage 42. When the passage 42 is positioned as far from the pivot point of valve element 25 as it can be moved. as shown in HO. 1, the minimum amount of valve element 25 movement will initiate the opening of passage 42. The control function is very sensitive. The value of the condition which will start the tilt of valve element 25 is set by the position of post 32. When this value of the condition changes slightly from that set by the position of post 32 (set point), valve 25 tilts a minimum but causes a large opening of passage 42. A large flow of fluid through the valve results.

The other extreme in the operation takes place when fixture 19 is rotated to bring passage 42 as close to the pivot point of valve 25 as possible. The valve element 25 has to tilt a relatively large amount to open the passage 42 significantly. A large change in the variable and thus a relatively large departure from the set point must occur to vary the flow of fluid through the valve over its full range.

Between the two extremes of settings for passage 42, the fixture 19 is rotated to obtain the desired relationship between the range of condition variation and the output fluid pressure. The device thus has two adjustments which make it an improved and more flexible tool for response to a variable condition. The value of the condition at which the output fluid pressure begins to change is established by setting the position of post 32 with knob 35. Then the range of change of output fluid pressure for the subsequent changes in condition is established by rotating fixture 19 to a preselected position.

lclaim:

l. A valve and actuating linkage, including:

a fixture providing a seat opening for the passage of fluid therethrough;

a valve element having:

a. a round flat base fitting over the seat opening and tiltable about any point on its round edge in function to vary the restriction of the seat opening;

b. and a protuberance extending from the middle of the base and with an axis at right angles to the plane of the base;

a link member axially aligned with the protuberance and with an axial hole journalled over the protuberance and movable axially to pivot and axially misalign with the valve element which exerts a transverse force on the protuberance with the wall of the hole to tilt the base about a point on its round edge to move the valve element from its fully seated position over the seat opening to a position which will restrict the seat opening;

a post adjustable along a line parallel with the valve element and link member in providing a pivot point for the link member which varies the position of the pivot point about which the link member is misaligned with the valve element protuberance;

and means for changing the position of the fixture to predetermine the distance between the seat opening and the point on the edge of the base of the valve element.

2. The valve and actuating linkage of claim 1 in which:

the fixture is axially aligned with the valve element and link member with a passage extending therethrough parallel with and offset from the axis and providing the seat opening; and

whereby rotation of the fixture as its change of position predetermines the distance between the seat opening and the point on the valve element base at which valve element tilts.

3. The valve and actuating linkage of claim 2 in which:

the rotatable fixture is extended to a location at which the fixture can be manually manipulated to rotate; and

a means is provided for visually indexing the position of the seat opening relative to the tilt point. 

